With a St. Louis loss giving them an opportunity to pull within a half-game of first place, the Astros collectively responded with something a lot stronger than “no, thank you.”

They sputtered at the plate and imploded on the mound as the recently hapless New York Mets laid on a 10-3 pounding in front of a sellout crowd of 43,302 at Minute Maid Park.

“Just not a good night offensively, or for that matter, pitching-wise,” Astros manager Cecil Cooper said.

Thanks to a three-run first by the Mets, the Astros took every swing of the night with a multiple-run deficit, and they never came close to doing anything about it. They were handcuffed by 22-year-old Mets starter Jonathon Niese, never getting more than one hit in an inning against the lefty.

But the Astros’ pitching performance made it so there would be no regret for one strikeout here or one double play there.

The regret belonged to Russ Ortiz, who was left lamenting four walks, three of which turned into runs.

Ortiz regressed after an encouraging loss in Los Angeles, giving up six earned runs on five hits in 41⁄3 taxing innings, which saw him throw 96 pitches.

“I actually felt great,” Ortiz said. “The thing I’m most frustrated about is that there were a couple guys I walked where I was ahead in the count or in good counts.”

He labored through a 27-pitch first inning, in part set up by a five-pitch walk to Luis Castillo. The Mets tallied on three consecutive plate appearances — an RBI double down the left-field line by Daniel Murphy, a Jeff Francoeur sacrifice fly and a Cory Sullivan RBI single.

But the more frustrating walk came in the fourth, when he had Sullivan down in the count 0-2 and walked him on 10 pitches.

Ortiz’s day ended in the fifth, perhaps fittingly, with an 11-pitch walk to David Wright, who fouled off five straight pitches. Francouer made him pay, sending reliever Tim Byrdak’s offering to the Crawford Boxes for a three-run shot that gave the Mets a 7-1 lead.

They cruised from there, snapping the Astros’ four-game winning streak and keeping them 11/2 games behind the National League Central-leading Cardinals and a game behind the Chicago Cubs, who won Saturday.

But Pence grounded out, and the Astros never got another walk, nor did they ever get another runner to second base against Niese. Pence’s two-run homer off Francisco Rodriguez in the ninth would be the only other offense the Astros amassed.

Niese, called up from Class AAA Buffalo before the game to make his sixth major league start, threw 106 pitches over seven innings. He allowed one run on four hits and two walks, striking out three.

“He just got ahead all the time,” said Ivan Rodriguez. “He basically did a great job, and the guys made good plays for him.”

One of those days

With the disparity in pitching performances early setting up plenty of low-leverage situations late, the Astros got Chad Paronto in to eat two innings before he was designated for assignment to make room for reliever Chris Sampson. Paronto allowed two runs, including a home run to Omir Santos, and the Mets capped their scoring in the ninth on Wright’s solo shot off Wesley Wright.

The three New York homers were a rare sight for a team that came in last in the league in home runs and hit multiple homers in a game for just the second time in July.

But for the Astros’ pitching staff, and really, the whole team, it was that sort of night.

Trading places

Relief pitcher Chris Sampson was activated from the disabled list after Saturday's game, and Chad Paronto was designated for assignment to clear space on the 25-man roster. Sampson had been on the 15-day DL since July 17 and hasn't pitched since July 10 with shoulder spasms. He was re-evaluated Saturday, one day after his lone simulated game.

"I feel all right," Sampson said. "It's a little sore, but I haven't really been on the mound facing hitters for a couple weeks, so that's to be expected.

The right-handed ground-ball specialist is still second on the club with 41 appearances — LaTroy Hawkins has 43 — and compiled a 3.02 ERA in 47 2/3 innings before going on the shelf.

Paronto pitched twice since his call-up, including two innings of mop-up work on Saturday night. The right-hander allowed six runs on seven hits in 2 1/3 innings after closing for Class AAA Round Rock for most of the season.